Risk associated in operation of Hydro jetting machines

Most of the process industries prefer to clean the heat exchangers tube and shell by high pressure (15000 psi to 20 000 psi) hydro jetting machines. This cleaning operation is having high potential for risk of human injury if due safety measures not taken by users. Any accidental contact of water jet would cause severe injury to human being sometimes it will be fatal also. The machine itself should be adequately equipped with safety features like pressure relief valve in pumping installation; recirculation system should be reliable, high pressure flexible hose connection should have flanged connection in place of threaded connections. The machine operator should wear Mandatory PPEs besides special PVC suits covering entire body. Area of work station should be barricaded properly to ensure that no one can approach the work place area.

During temporary idling of cleaning operation, pumping system should be kept in circulation and main stream of jet should be kept off to avoid any accident.

One standby man should stand near control panel for emergency stop of the motor. He should also be in proper PPEs.

Arresting minor leak by OLS (On line sealing) clamp on pipe lines handling HC fluid

1. Firstly  make attempt to temporary seal the minor leak/seepage by applying  cold 5 minutes putty.

2. Carry out thorough thickness measurement by UT (Ultrasonic Testing) detector covering surface area at distance of 150 mm (minimum) from the leak spot.

3. If thickness reduction is not significant (i.e. not below the nominal thickness minus corrosion allowance),we can proceed for installing suitably designed two halves bolted  clamps on leak spot with provision for injecting the furmaniting  compound at pressure not above 30% of operating pressure.

4. Inject furmaniting compound as explained above.

5. This will work for 12 month with periodical top up of furmaniting compound at interval of every 3 months.

6. Normalize pipe line (i.e.remove clamp)  and replace leaking pipe in next S/D opportunity for long term reliability.